Double-sided fan



FIG. 1 is a perspective view of the double-sided fan showing my new design;

FIG. 2 is a front elevational view thereof, the rear elevational view being substantially a mirror image of the view shown in this Figure;

FIG. 3 is a right side elevational view thereof, the left side elevational view being substanially a mirror image of the view shown in this Figure;

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a double-sided fan, as shown and described. 